Benjamin le coultee



(No Model.)

B. LE COULTRE.

SAFETY PINION POB WATCHES.

No. 358,208. Patented Fab. 22, 1887.

PLPCTERS, Pholfrb-Lihogmpher Wnhingnn. C.

UNITED STATES PATENT OEEICE.

BENJAMIN LE COULTRE, OF SENTIER, SWITZERLAND.

SAFETY-PINION FOR WATCHES.

SPECIFICATION forming part of Letters Patent No. 358,208, dated February 22, 1887.

Application filed October 19, 1886. Serial No. M6182.

.To @ZZ whom, it may concern:

Be it known that I, BENJAMIN LE COULTRE,

a citizen of Switzerland, and a resident of Sentier, in theRepublic of Switzerland, have in- Vented certain new and useful Improvements in Safety/Pinions for Vatches, of which the following is a specification.

The object of my invention is to provide a new and improved safety-pinion of such a construction that the pinion can be released from the arbor with a few turns backward from the arbor, whereby the pinion is raised only the distance of the height of 011e of the screws, in contradistinction to the well-known Fogg pinion, which requires that the pinion should be unscrewed to its 'full depth to release it from the arbor when the recoil of the rnainspring in breaking turns the pinion in its unscrewing direction.

The invention consists in the combination, with an arbor having two screw-threads, of a tubular pinion having two internal screwthreads adapted to engage with the screwthreads on the arb'or, whereby when the spring is not broken the tubular pinion is held securely on the arbor, but when the mainspring breaks the force of the recoil is sufficient to revolve the pinion and nnscrew it from its arbor, all as will be fully described and set forth hereinafter, and tinally pointed out in the claim.

Inthe accompanying drawings, Figure l is a side View of the arbor ot' my improved safetypinion. Fig. 2 is a top view of the tubular pinion. Fig. 3 is a side view of the same, parts being broken out.

Similar letters of reference indicate corresponding parts.

The arbor A is provided with two screwthreaded collars, c and b, at a short distance from each other, and at the bottom of the screwthreaded collar b a shoulder or offset, B, is formed, against which the bottom of the pinion D, that is provided with top and bot- (No model.)

tom interior screw-threaded collars c and d, can rest.

As shown in Fig. 1, the diameter of the arbor is less between the screw-collars a and b than at said collars, and, as shown in Fig. 3, the internal diameter of the tubular pinion D is greater between the collars c and d than at said collars. The screw-threads on the several collars of the arbor and pinion are right or left, according to the direction in whichthe spring coils. The tubular pinion is screwed on the arbor, the screw-threaded collars of the pinion engaging the screw-threaded collars of the arbor, and as long as the spring is intact the pinion is screwed down, so as to rest on the offset or shoulder B; but whenever the mainspring breaks the force of the recoil causes the pinion to revolve in theinverse direction,whereht1 said pinion is nnscrewed from thc arbor, and the screw-threaded collar a of the arbor is now in the recess in the pinion and the bottom screw-threaded collar d of the pinion is in the spacebetween the collars a and b of the arbor.

The pinion revolves without revolving the arborA, and all danger of derangeinent and breaking of the gear is avoided.

Having thus described my invention, I claim as new and desire to secure by Letters Patent A safety-pinion for watches,consisting of an arbor provided with two threaded collars a short distance from each other, and atubular pinion provided with two screw-threaded internal collars, separated the same distance from each other as the collars on the arbor, substantially as shown and described.

Signed at ChauX-de-Fonds, in the canton of Neuchatel and Republic of Switzerland, this 24th day of May, A. D. 1886.

BENJAMIN LE COULTRE.

li l-nesses:

L. Bozar, JAarEs BOILLAT. 

